MPEG-1 is a multimedia transmission system that allows the combining and synchronizing of multiple media types (e.g. digital audio and digital video). MPEG-1 was primarily developed for CD-ROM multimedia applications. Because it is primarily focused on multimedia computers, there is no defined way to process interlaced video. The compression processes used in MPEG-1 systems can compress digital video up to 52 to 1.

Media Multiplexing - Part 1 of the MPEG-1 specification defines the overall system operation. It explains how the audio and video streams are combined into a single data stream and how these streams are separated, decoded and time synchronized.

Low Complexity Video Compression - Part 2 defines how digital video is coded for compressing video sequences allowing bit rates up to 1.5 Mbps. This standard defines the use of spatial (image compression) and temporal (multiple sequences) through the use of image blocks and a prediction of how these blocks will move between frames.

Part 3 defines how audio is compressed. There are 3 levels of audio compression defined in part 3 ranging from the least complex (lowest compression ratio) to the most complex (highest compression ratio). The most complex, level 3, is the origin of MPEG-1, part 3 (MP3).

Stored Media Distribution - Stored media distribution is the process of providing content to one or more persons or companies through the use of storage devices (such as CD ROMs or DVDs). Stored media distribution systems contain content in standard formats (such as MPEG).

Part 4 defines how bit streams and decoders can be tested to meet MPEG specification requirements. Part 5 provides software simulations for the MPEG-1 system.